Improved survival in pediatric acute lymphoblastic leukemia through therapy intensification based on minimal residual disease and protocol‑driven early response risk classification
10.1007/s44313-025-00085-3
- Author:
Hyery KIM
1
;
Su Hyun YOON
;
Sunghan KANG
;
Kyung‑Nam KOH
;
Ho Joon IM
;
Daehyun CHU
;
Mi Young KIM
;
Young‑Uk CHO
;
Sang‑Hyun HWANG
;
Seongsoo JANG
Author Information
1. Department of Pediatrics, University of Ulsan College of Medicine, Asan Medical Center, Seoul, South Korea
- Publication Type:RESEARCH
- From:Blood Research
2025;60():40-
- CountryRepublic of Korea
- Language:English
-
Abstract:
Purpose:Minimal residual disease (MRD)-guided therapy is the global standard treatment for pediatric acute lymphoblastic leukemia (ALL). We assessed the impact of MRD-driven intensification along with protocol-defined risk groups in pediatric ALL treatment.
Methods:This retrospective analysis included 209 patients with ALL (treated between January 2013 to June 2023).MRD was assessed using six- to eight-color flow cytometry at the end of each phase before the maintenance phase.Post-induction treatment was determined based on early response, National Cancer Institute risk, and cytogenet‑ ics. High-risk (HR) patients followed the Korean HR or CCG-1882 protocols and standard-risk (SR) patients followed the modified COG-AALL0331 protocol. Treatment was intensified if flow-MRD ≥ 0.1% was identified.
Results:Overall, 103 and 106 patients were classified as having SR and HR, respectively. The 5-year overall survival (OS) and event-free survival (EFS) were 92.5% and 84.3%, respectively. Thirty SR and 18 HR patients received intensi‑ fied chemotherapy. Treatment intensification significantly improved EFS in patients with high MRD (94.2% vs. 75.5%, p = 0.04), particularly in post-induction patients with high MRD (90.0% vs. 19.0%, p = 0.035). The difference in survival between rapid early responder (RER) and slow early responder (SER) groups was eliminated after MRD-based intensifi‑ cation. The implementation rates of treatment intensification varied over time (9.1% before 2015, 28.6% during 2016– 2019, and 13.9% during 2020–2023), reflecting improved risk stratification and therapy selection.
Conclusion:MRD-guided therapy intensification markedly improved survival outcomes in patients with pediatric ALL when combined with risk-based protocols, highlighting the importance of MRD monitoring for optimizing riskadapted treatment strategies.
